Instrumentation Amplifier

with an electrically isolated input

The instrumentation amplifier described here has two important features. Its input is electrically isolated and it has no fewer than 16 input and output ranges that can be selected for many types of signal conversion.Most commercial instrumentation amplifiers provide a number of input ranges, but their outputs are usually restricted to one or two voltage ranges and a similar number of current ranges. In this circuit there is a wide choice of input and output ranges: seven unipolar voltage ranges (varying from 0 to 100 mV to 0 to 10 V), seven bipolar voltage ranges (±100 mV to ±10 V) and two current ranges (0 to 20 mA and 4 to 20 mA). The output can be chosen to follow the input on a 1:1 basis, but conversion between any of the ranges is also possible.